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Posted to hdfs-user@hadoop.apache.org by Amjad ALSHABANI <as...@gmail.com> on 2014/06/02 10:01:24 UTC
Re: HDFS undo Overwriting
Thanx Zesheng,
I should admit that I m not an expert in Hadoop infrastructure, but I have
heard my colleagues talking about HDFS replicas?
Couldn't that help in retrieving the lost data??
Amjad
On Fri, May 30, 2014 at 1:44 PM, Zesheng Wu <wu...@gmail.com> wrote:
> I am afraid this cannot undo, in HDFS only the data which is deleted by
> the dfs client and goes into the trash can be undone.
>
>
> 2014-05-30 18:18 GMT+08:00 Amjad ALSHABANI <as...@gmail.com>:
>
> Hello Everybody,
>>
>> I ve made a mistake when writing to HDFS. I created new database in Hive
>> giving the location on HDFS but I found that it removed all other data that
>> exist already.
>>
>> =====
>> before creation, the directory on HDFS contains :
>> pns@app11:~$ hadoop fs -ls /user/hive/warehouse
>> Found 25 items
>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>> */user/hive/warehouse/*dfy_ans_autres
>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>> /user/hive/warehouse/dfy_ans_maillog
>> drwxr-xr-x - user1 supergroup 0 2013-11-20 14:28
>> /user/hive/warehouse/dfy_cnx
>> drwxr-xr-x - user2 supergroup 0 2014-05-30 06:05
>> /user/hive/warehouse/pns.db
>> drwxr-xr-x - user2 supergroup 0 2014-02-24 17:00
>> /user/hive/warehouse/pns_fr_integ
>> drwxr-xr-x - user2 supergroup 0 2014-05-06 15:33
>> /user/hive/warehouse/pns_logstat.db
>> ...
>> ...
>> ...
>>
>>
>> hive -e "CREATE DATABASE my_stats LOCATION 'hdfs://XXXX:9000
>> */user/hive/warehouse/*mystats.db'"
>>
>> but now I couldn't see the other directories on HDFS:
>>
>> pns@app11:~/aalshabani$ hls /user/hive/warehouse
>> Found 1 items
>> drwxr-xr-x - user2 supergroup 0 2014-05-30 11:37
>> */user/hive/warehouse*/mystats.db
>>
>>
>> Is there anyway I could restore the other directories??
>>
>>
>> Best regards.
>>
>
>
>
> --
> Best Wishes!
>
> Yours, Zesheng
>
Re: HDFS undo Overwriting
Posted by Amr Shahin <am...@gmail.com>.
There is no built in functionality in HDFS to do this. However, there are
some software that can restore the hard-drive to a previous date (they work
on the OS level transparent to HDFS), you might wanna try one of those. Not
sure how the namenode will react to this though, you could at least get the
old raw data and figure something out after that.
On Mon, Jun 2, 2014 at 1:40 PM, varun kumar <va...@gmail.com> wrote:
> Nope.
>
> Sorry :(
>
>
> On Mon, Jun 2, 2014 at 1:31 PM, Amjad ALSHABANI <as...@gmail.com>
> wrote:
>
>> Thanx Zesheng,
>>
>> I should admit that I m not an expert in Hadoop infrastructure, but I
>> have heard my colleagues talking about HDFS replicas?
>> Couldn't that help in retrieving the lost data??
>>
>> Amjad
>>
>>
>> On Fri, May 30, 2014 at 1:44 PM, Zesheng Wu <wu...@gmail.com>
>> wrote:
>>
>>> I am afraid this cannot undo, in HDFS only the data which is deleted by
>>> the dfs client and goes into the trash can be undone.
>>>
>>>
>>> 2014-05-30 18:18 GMT+08:00 Amjad ALSHABANI <as...@gmail.com>:
>>>
>>> Hello Everybody,
>>>>
>>>> I ve made a mistake when writing to HDFS. I created new database in
>>>> Hive giving the location on HDFS but I found that it removed all other data
>>>> that exist already.
>>>>
>>>> =====
>>>> before creation, the directory on HDFS contains :
>>>> pns@app11:~$ hadoop fs -ls /user/hive/warehouse
>>>> Found 25 items
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>>> */user/hive/warehouse/*dfy_ans_autres
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>>> /user/hive/warehouse/dfy_ans_maillog
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 14:28
>>>> /user/hive/warehouse/dfy_cnx
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 06:05
>>>> /user/hive/warehouse/pns.db
>>>> drwxr-xr-x - user2 supergroup 0 2014-02-24 17:00
>>>> /user/hive/warehouse/pns_fr_integ
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-06 15:33
>>>> /user/hive/warehouse/pns_logstat.db
>>>> ...
>>>> ...
>>>> ...
>>>>
>>>>
>>>> hive -e "CREATE DATABASE my_stats LOCATION 'hdfs://XXXX:9000
>>>> */user/hive/warehouse/*mystats.db'"
>>>>
>>>> but now I couldn't see the other directories on HDFS:
>>>>
>>>> pns@app11:~/aalshabani$ hls /user/hive/warehouse
>>>> Found 1 items
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 11:37
>>>> */user/hive/warehouse*/mystats.db
>>>>
>>>>
>>>> Is there anyway I could restore the other directories??
>>>>
>>>>
>>>> Best regards.
>>>>
>>>
>>>
>>>
>>> --
>>> Best Wishes!
>>>
>>> Yours, Zesheng
>>>
>>
>>
>
>
> --
> Regards,
> Varun Kumar.P
>
Re: HDFS undo Overwriting
Posted by Amr Shahin <am...@gmail.com>.
There is no built in functionality in HDFS to do this. However, there are
some software that can restore the hard-drive to a previous date (they work
on the OS level transparent to HDFS), you might wanna try one of those. Not
sure how the namenode will react to this though, you could at least get the
old raw data and figure something out after that.
On Mon, Jun 2, 2014 at 1:40 PM, varun kumar <va...@gmail.com> wrote:
> Nope.
>
> Sorry :(
>
>
> On Mon, Jun 2, 2014 at 1:31 PM, Amjad ALSHABANI <as...@gmail.com>
> wrote:
>
>> Thanx Zesheng,
>>
>> I should admit that I m not an expert in Hadoop infrastructure, but I
>> have heard my colleagues talking about HDFS replicas?
>> Couldn't that help in retrieving the lost data??
>>
>> Amjad
>>
>>
>> On Fri, May 30, 2014 at 1:44 PM, Zesheng Wu <wu...@gmail.com>
>> wrote:
>>
>>> I am afraid this cannot undo, in HDFS only the data which is deleted by
>>> the dfs client and goes into the trash can be undone.
>>>
>>>
>>> 2014-05-30 18:18 GMT+08:00 Amjad ALSHABANI <as...@gmail.com>:
>>>
>>> Hello Everybody,
>>>>
>>>> I ve made a mistake when writing to HDFS. I created new database in
>>>> Hive giving the location on HDFS but I found that it removed all other data
>>>> that exist already.
>>>>
>>>> =====
>>>> before creation, the directory on HDFS contains :
>>>> pns@app11:~$ hadoop fs -ls /user/hive/warehouse
>>>> Found 25 items
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>>> */user/hive/warehouse/*dfy_ans_autres
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>>> /user/hive/warehouse/dfy_ans_maillog
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 14:28
>>>> /user/hive/warehouse/dfy_cnx
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 06:05
>>>> /user/hive/warehouse/pns.db
>>>> drwxr-xr-x - user2 supergroup 0 2014-02-24 17:00
>>>> /user/hive/warehouse/pns_fr_integ
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-06 15:33
>>>> /user/hive/warehouse/pns_logstat.db
>>>> ...
>>>> ...
>>>> ...
>>>>
>>>>
>>>> hive -e "CREATE DATABASE my_stats LOCATION 'hdfs://XXXX:9000
>>>> */user/hive/warehouse/*mystats.db'"
>>>>
>>>> but now I couldn't see the other directories on HDFS:
>>>>
>>>> pns@app11:~/aalshabani$ hls /user/hive/warehouse
>>>> Found 1 items
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 11:37
>>>> */user/hive/warehouse*/mystats.db
>>>>
>>>>
>>>> Is there anyway I could restore the other directories??
>>>>
>>>>
>>>> Best regards.
>>>>
>>>
>>>
>>>
>>> --
>>> Best Wishes!
>>>
>>> Yours, Zesheng
>>>
>>
>>
>
>
> --
> Regards,
> Varun Kumar.P
>
Re: HDFS undo Overwriting
Posted by Amr Shahin <am...@gmail.com>.
There is no built in functionality in HDFS to do this. However, there are
some software that can restore the hard-drive to a previous date (they work
on the OS level transparent to HDFS), you might wanna try one of those. Not
sure how the namenode will react to this though, you could at least get the
old raw data and figure something out after that.
On Mon, Jun 2, 2014 at 1:40 PM, varun kumar <va...@gmail.com> wrote:
> Nope.
>
> Sorry :(
>
>
> On Mon, Jun 2, 2014 at 1:31 PM, Amjad ALSHABANI <as...@gmail.com>
> wrote:
>
>> Thanx Zesheng,
>>
>> I should admit that I m not an expert in Hadoop infrastructure, but I
>> have heard my colleagues talking about HDFS replicas?
>> Couldn't that help in retrieving the lost data??
>>
>> Amjad
>>
>>
>> On Fri, May 30, 2014 at 1:44 PM, Zesheng Wu <wu...@gmail.com>
>> wrote:
>>
>>> I am afraid this cannot undo, in HDFS only the data which is deleted by
>>> the dfs client and goes into the trash can be undone.
>>>
>>>
>>> 2014-05-30 18:18 GMT+08:00 Amjad ALSHABANI <as...@gmail.com>:
>>>
>>> Hello Everybody,
>>>>
>>>> I ve made a mistake when writing to HDFS. I created new database in
>>>> Hive giving the location on HDFS but I found that it removed all other data
>>>> that exist already.
>>>>
>>>> =====
>>>> before creation, the directory on HDFS contains :
>>>> pns@app11:~$ hadoop fs -ls /user/hive/warehouse
>>>> Found 25 items
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>>> */user/hive/warehouse/*dfy_ans_autres
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>>> /user/hive/warehouse/dfy_ans_maillog
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 14:28
>>>> /user/hive/warehouse/dfy_cnx
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 06:05
>>>> /user/hive/warehouse/pns.db
>>>> drwxr-xr-x - user2 supergroup 0 2014-02-24 17:00
>>>> /user/hive/warehouse/pns_fr_integ
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-06 15:33
>>>> /user/hive/warehouse/pns_logstat.db
>>>> ...
>>>> ...
>>>> ...
>>>>
>>>>
>>>> hive -e "CREATE DATABASE my_stats LOCATION 'hdfs://XXXX:9000
>>>> */user/hive/warehouse/*mystats.db'"
>>>>
>>>> but now I couldn't see the other directories on HDFS:
>>>>
>>>> pns@app11:~/aalshabani$ hls /user/hive/warehouse
>>>> Found 1 items
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 11:37
>>>> */user/hive/warehouse*/mystats.db
>>>>
>>>>
>>>> Is there anyway I could restore the other directories??
>>>>
>>>>
>>>> Best regards.
>>>>
>>>
>>>
>>>
>>> --
>>> Best Wishes!
>>>
>>> Yours, Zesheng
>>>
>>
>>
>
>
> --
> Regards,
> Varun Kumar.P
>
Re: HDFS undo Overwriting
Posted by Amr Shahin <am...@gmail.com>.
There is no built in functionality in HDFS to do this. However, there are
some software that can restore the hard-drive to a previous date (they work
on the OS level transparent to HDFS), you might wanna try one of those. Not
sure how the namenode will react to this though, you could at least get the
old raw data and figure something out after that.
On Mon, Jun 2, 2014 at 1:40 PM, varun kumar <va...@gmail.com> wrote:
> Nope.
>
> Sorry :(
>
>
> On Mon, Jun 2, 2014 at 1:31 PM, Amjad ALSHABANI <as...@gmail.com>
> wrote:
>
>> Thanx Zesheng,
>>
>> I should admit that I m not an expert in Hadoop infrastructure, but I
>> have heard my colleagues talking about HDFS replicas?
>> Couldn't that help in retrieving the lost data??
>>
>> Amjad
>>
>>
>> On Fri, May 30, 2014 at 1:44 PM, Zesheng Wu <wu...@gmail.com>
>> wrote:
>>
>>> I am afraid this cannot undo, in HDFS only the data which is deleted by
>>> the dfs client and goes into the trash can be undone.
>>>
>>>
>>> 2014-05-30 18:18 GMT+08:00 Amjad ALSHABANI <as...@gmail.com>:
>>>
>>> Hello Everybody,
>>>>
>>>> I ve made a mistake when writing to HDFS. I created new database in
>>>> Hive giving the location on HDFS but I found that it removed all other data
>>>> that exist already.
>>>>
>>>> =====
>>>> before creation, the directory on HDFS contains :
>>>> pns@app11:~$ hadoop fs -ls /user/hive/warehouse
>>>> Found 25 items
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>>> */user/hive/warehouse/*dfy_ans_autres
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>>> /user/hive/warehouse/dfy_ans_maillog
>>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 14:28
>>>> /user/hive/warehouse/dfy_cnx
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 06:05
>>>> /user/hive/warehouse/pns.db
>>>> drwxr-xr-x - user2 supergroup 0 2014-02-24 17:00
>>>> /user/hive/warehouse/pns_fr_integ
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-06 15:33
>>>> /user/hive/warehouse/pns_logstat.db
>>>> ...
>>>> ...
>>>> ...
>>>>
>>>>
>>>> hive -e "CREATE DATABASE my_stats LOCATION 'hdfs://XXXX:9000
>>>> */user/hive/warehouse/*mystats.db'"
>>>>
>>>> but now I couldn't see the other directories on HDFS:
>>>>
>>>> pns@app11:~/aalshabani$ hls /user/hive/warehouse
>>>> Found 1 items
>>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 11:37
>>>> */user/hive/warehouse*/mystats.db
>>>>
>>>>
>>>> Is there anyway I could restore the other directories??
>>>>
>>>>
>>>> Best regards.
>>>>
>>>
>>>
>>>
>>> --
>>> Best Wishes!
>>>
>>> Yours, Zesheng
>>>
>>
>>
>
>
> --
> Regards,
> Varun Kumar.P
>
Re: HDFS undo Overwriting
Posted by varun kumar <va...@gmail.com>.
Nope.
Sorry :(
On Mon, Jun 2, 2014 at 1:31 PM, Amjad ALSHABANI <as...@gmail.com>
wrote:
> Thanx Zesheng,
>
> I should admit that I m not an expert in Hadoop infrastructure, but I have
> heard my colleagues talking about HDFS replicas?
> Couldn't that help in retrieving the lost data??
>
> Amjad
>
>
> On Fri, May 30, 2014 at 1:44 PM, Zesheng Wu <wu...@gmail.com> wrote:
>
>> I am afraid this cannot undo, in HDFS only the data which is deleted by
>> the dfs client and goes into the trash can be undone.
>>
>>
>> 2014-05-30 18:18 GMT+08:00 Amjad ALSHABANI <as...@gmail.com>:
>>
>> Hello Everybody,
>>>
>>> I ve made a mistake when writing to HDFS. I created new database in Hive
>>> giving the location on HDFS but I found that it removed all other data that
>>> exist already.
>>>
>>> =====
>>> before creation, the directory on HDFS contains :
>>> pns@app11:~$ hadoop fs -ls /user/hive/warehouse
>>> Found 25 items
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>> */user/hive/warehouse/*dfy_ans_autres
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>> /user/hive/warehouse/dfy_ans_maillog
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 14:28
>>> /user/hive/warehouse/dfy_cnx
>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 06:05
>>> /user/hive/warehouse/pns.db
>>> drwxr-xr-x - user2 supergroup 0 2014-02-24 17:00
>>> /user/hive/warehouse/pns_fr_integ
>>> drwxr-xr-x - user2 supergroup 0 2014-05-06 15:33
>>> /user/hive/warehouse/pns_logstat.db
>>> ...
>>> ...
>>> ...
>>>
>>>
>>> hive -e "CREATE DATABASE my_stats LOCATION 'hdfs://XXXX:9000
>>> */user/hive/warehouse/*mystats.db'"
>>>
>>> but now I couldn't see the other directories on HDFS:
>>>
>>> pns@app11:~/aalshabani$ hls /user/hive/warehouse
>>> Found 1 items
>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 11:37
>>> */user/hive/warehouse*/mystats.db
>>>
>>>
>>> Is there anyway I could restore the other directories??
>>>
>>>
>>> Best regards.
>>>
>>
>>
>>
>> --
>> Best Wishes!
>>
>> Yours, Zesheng
>>
>
>
--
Regards,
Varun Kumar.P
Re: HDFS undo Overwriting
Posted by varun kumar <va...@gmail.com>.
Nope.
Sorry :(
On Mon, Jun 2, 2014 at 1:31 PM, Amjad ALSHABANI <as...@gmail.com>
wrote:
> Thanx Zesheng,
>
> I should admit that I m not an expert in Hadoop infrastructure, but I have
> heard my colleagues talking about HDFS replicas?
> Couldn't that help in retrieving the lost data??
>
> Amjad
>
>
> On Fri, May 30, 2014 at 1:44 PM, Zesheng Wu <wu...@gmail.com> wrote:
>
>> I am afraid this cannot undo, in HDFS only the data which is deleted by
>> the dfs client and goes into the trash can be undone.
>>
>>
>> 2014-05-30 18:18 GMT+08:00 Amjad ALSHABANI <as...@gmail.com>:
>>
>> Hello Everybody,
>>>
>>> I ve made a mistake when writing to HDFS. I created new database in Hive
>>> giving the location on HDFS but I found that it removed all other data that
>>> exist already.
>>>
>>> =====
>>> before creation, the directory on HDFS contains :
>>> pns@app11:~$ hadoop fs -ls /user/hive/warehouse
>>> Found 25 items
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>> */user/hive/warehouse/*dfy_ans_autres
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>> /user/hive/warehouse/dfy_ans_maillog
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 14:28
>>> /user/hive/warehouse/dfy_cnx
>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 06:05
>>> /user/hive/warehouse/pns.db
>>> drwxr-xr-x - user2 supergroup 0 2014-02-24 17:00
>>> /user/hive/warehouse/pns_fr_integ
>>> drwxr-xr-x - user2 supergroup 0 2014-05-06 15:33
>>> /user/hive/warehouse/pns_logstat.db
>>> ...
>>> ...
>>> ...
>>>
>>>
>>> hive -e "CREATE DATABASE my_stats LOCATION 'hdfs://XXXX:9000
>>> */user/hive/warehouse/*mystats.db'"
>>>
>>> but now I couldn't see the other directories on HDFS:
>>>
>>> pns@app11:~/aalshabani$ hls /user/hive/warehouse
>>> Found 1 items
>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 11:37
>>> */user/hive/warehouse*/mystats.db
>>>
>>>
>>> Is there anyway I could restore the other directories??
>>>
>>>
>>> Best regards.
>>>
>>
>>
>>
>> --
>> Best Wishes!
>>
>> Yours, Zesheng
>>
>
>
--
Regards,
Varun Kumar.P
Re: HDFS undo Overwriting
Posted by varun kumar <va...@gmail.com>.
Nope.
Sorry :(
On Mon, Jun 2, 2014 at 1:31 PM, Amjad ALSHABANI <as...@gmail.com>
wrote:
> Thanx Zesheng,
>
> I should admit that I m not an expert in Hadoop infrastructure, but I have
> heard my colleagues talking about HDFS replicas?
> Couldn't that help in retrieving the lost data??
>
> Amjad
>
>
> On Fri, May 30, 2014 at 1:44 PM, Zesheng Wu <wu...@gmail.com> wrote:
>
>> I am afraid this cannot undo, in HDFS only the data which is deleted by
>> the dfs client and goes into the trash can be undone.
>>
>>
>> 2014-05-30 18:18 GMT+08:00 Amjad ALSHABANI <as...@gmail.com>:
>>
>> Hello Everybody,
>>>
>>> I ve made a mistake when writing to HDFS. I created new database in Hive
>>> giving the location on HDFS but I found that it removed all other data that
>>> exist already.
>>>
>>> =====
>>> before creation, the directory on HDFS contains :
>>> pns@app11:~$ hadoop fs -ls /user/hive/warehouse
>>> Found 25 items
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>> */user/hive/warehouse/*dfy_ans_autres
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>> /user/hive/warehouse/dfy_ans_maillog
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 14:28
>>> /user/hive/warehouse/dfy_cnx
>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 06:05
>>> /user/hive/warehouse/pns.db
>>> drwxr-xr-x - user2 supergroup 0 2014-02-24 17:00
>>> /user/hive/warehouse/pns_fr_integ
>>> drwxr-xr-x - user2 supergroup 0 2014-05-06 15:33
>>> /user/hive/warehouse/pns_logstat.db
>>> ...
>>> ...
>>> ...
>>>
>>>
>>> hive -e "CREATE DATABASE my_stats LOCATION 'hdfs://XXXX:9000
>>> */user/hive/warehouse/*mystats.db'"
>>>
>>> but now I couldn't see the other directories on HDFS:
>>>
>>> pns@app11:~/aalshabani$ hls /user/hive/warehouse
>>> Found 1 items
>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 11:37
>>> */user/hive/warehouse*/mystats.db
>>>
>>>
>>> Is there anyway I could restore the other directories??
>>>
>>>
>>> Best regards.
>>>
>>
>>
>>
>> --
>> Best Wishes!
>>
>> Yours, Zesheng
>>
>
>
--
Regards,
Varun Kumar.P
Re: HDFS undo Overwriting
Posted by varun kumar <va...@gmail.com>.
Nope.
Sorry :(
On Mon, Jun 2, 2014 at 1:31 PM, Amjad ALSHABANI <as...@gmail.com>
wrote:
> Thanx Zesheng,
>
> I should admit that I m not an expert in Hadoop infrastructure, but I have
> heard my colleagues talking about HDFS replicas?
> Couldn't that help in retrieving the lost data??
>
> Amjad
>
>
> On Fri, May 30, 2014 at 1:44 PM, Zesheng Wu <wu...@gmail.com> wrote:
>
>> I am afraid this cannot undo, in HDFS only the data which is deleted by
>> the dfs client and goes into the trash can be undone.
>>
>>
>> 2014-05-30 18:18 GMT+08:00 Amjad ALSHABANI <as...@gmail.com>:
>>
>> Hello Everybody,
>>>
>>> I ve made a mistake when writing to HDFS. I created new database in Hive
>>> giving the location on HDFS but I found that it removed all other data that
>>> exist already.
>>>
>>> =====
>>> before creation, the directory on HDFS contains :
>>> pns@app11:~$ hadoop fs -ls /user/hive/warehouse
>>> Found 25 items
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>> */user/hive/warehouse/*dfy_ans_autres
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 13:40
>>> /user/hive/warehouse/dfy_ans_maillog
>>> drwxr-xr-x - user1 supergroup 0 2013-11-20 14:28
>>> /user/hive/warehouse/dfy_cnx
>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 06:05
>>> /user/hive/warehouse/pns.db
>>> drwxr-xr-x - user2 supergroup 0 2014-02-24 17:00
>>> /user/hive/warehouse/pns_fr_integ
>>> drwxr-xr-x - user2 supergroup 0 2014-05-06 15:33
>>> /user/hive/warehouse/pns_logstat.db
>>> ...
>>> ...
>>> ...
>>>
>>>
>>> hive -e "CREATE DATABASE my_stats LOCATION 'hdfs://XXXX:9000
>>> */user/hive/warehouse/*mystats.db'"
>>>
>>> but now I couldn't see the other directories on HDFS:
>>>
>>> pns@app11:~/aalshabani$ hls /user/hive/warehouse
>>> Found 1 items
>>> drwxr-xr-x - user2 supergroup 0 2014-05-30 11:37
>>> */user/hive/warehouse*/mystats.db
>>>
>>>
>>> Is there anyway I could restore the other directories??
>>>
>>>
>>> Best regards.
>>>
>>
>>
>>
>> --
>> Best Wishes!
>>
>> Yours, Zesheng
>>
>
>
--
Regards,
Varun Kumar.P